Certain materials (such as brittle materials, for example white cast iron) are cast in a mould and then allowed to solidify and cool in the mould over a number of days/weeks. For example, when a thick section (say, >150 mm) white cast iron component is cast from molten metal and placed in a sand mould, to avoid cracking it may be allowed to solidify and cool in the mould over a long period (in extreme cases up to around fourteen days). Slow cooling is employed to prevent cracking of the resulting component which can occur if the component is removed from the mould too early and exposed to the atmosphere for a time. However, a long cooling time results in significant delays in the production process, as well as occupying capital equipment and space.
U.S. Pat. No. 6,199,618, EP 625390, GB1600405 and JP 04-344859 each disclose controlled cooling processes and apparatus for castings. In each case the casting is conveyed through successively cooled stages of oven-like apparatus.
A reference herein to the prior art is not an admission that the prior art forms part of the common general knowledge of a person of ordinary skill in the art in Australia or elsewhere.